Health Officials Address Rare Measles Cases Among Vaccinated as L.A. County Remains Vigilant

As measles cases in the United States surpass 800 since the beginning of the year, health officials are addressing concerns about rare “breakthrough infections” that occur in fully vaccinated individuals. For Inglewood and Compton families seeking to protect their children and themselves, understanding these breakthrough cases is an important part of overall health awareness.

While the majority of the current nationwide measles cases are among unvaccinated individuals, approximately 3% are breakthrough infections, where people got sick despite being either partially or fully vaccinated with the measles, mumps and rubella (MMR) shot.

“These breakthrough infection statistics are actually reassuring evidence of how effective the measles vaccine is,” said Dr. Amelia Rodriguez, a pediatrician at the Inglewood Community Health Center. “We’re seeing over 97% protection, which is remarkable for any vaccine, and even those few breakthrough cases typically experience much milder symptoms.”

Local health departments emphasize that one dose of the MMR vaccine is 93% effective at preventing measles, with the second dose increasing that to 97%.

“The vaccine is highly effective,” explains Rodney Rohde, a professor at Texas State University. “But it means that after two doses, while 97 out of 100 people will develop strong immunity and be protected if exposed to measles, the remaining three out of 100 could still be vulnerable.”

For Inglewood families, the message from medical professionals remains clear: vaccination is the best protection against measles, which is one of the most contagious diseases known to medicine.

When breakthrough infections do occur in vaccinated individuals, the disease is typically much milder. “If someone vaccinated does get measles, it’s often a less severe version, sometimes called modified measles,” says Rohde. “A rash can still occur, but it may be less widespread, fainter or atypical. Fever is also less common or lower-grade.”

Other common measles symptoms like cough, runny nose, and red eyes may still occur in breakthrough cases, but are often less intense. These cases are also generally less contagious, though they can still potentially transmit the virus.

The Los Angeles County Department of Public Health confirms that no measles cases have been reported in Inglewood or Compton so far this year, but officials continue to monitor the situation closely as outbreaks persist in other parts of the country.

Scientists have identified several factors that may contribute to breakthrough infections:

Timing of Vaccination: People who have just received the MMR vaccine remain vulnerable for about two weeks while their immune system builds protection. If exposed during this window, infection is still possible.

Individual Immune Response: Due to genetic variability, a small percentage of people may not develop a robust immune response to the vaccine.

Immune System Status: People with compromised immune systems due to certain medical conditions or treatments may not be as well protected even if fully vaccinated.

Contrary to some claims circulating on social media, scientists emphasize that the MMR vaccine offers long-lasting protection. “If immunity waned a lot, you would see a lot of cases in vaccinated people in older age groups, and we’re not seeing that,” said Scott Weaver, a microbiology and immunology professor at the University of Texas Medical Branch.

Health officials in Los Angeles County recommend that residents check their vaccination status, especially if they were born between 1957 and 1989. People born between 1957 and 1968 may have received a first-generation measles vaccine that was less effective, while those born between 1968 and 1989 may have received only one dose instead of the currently recommended two doses.

“Even if you’re truly immune and you get another dose of MMR, there’s no harm to that,” said Dr. William Schaffner, a professor of preventive medicine and infectious diseases at Vanderbilt University School of Medicine.

Inglewood residents can access MMR vaccines at the Inglewood Community Health Center, MLK Jr. Outpatient Center, and various local pharmacies. Most insurance plans cover the vaccine, and programs are available for those without insurance.

The Inglewood Unified School District continues to work with health officials to ensure high vaccination rates among students. Current district records show a 94% MMR vaccination rate among enrolled students, slightly above the Los Angeles County average.

For more information about measles vaccination or to schedule an appointment, residents can contact the Los Angeles County Department of Public Health at (213) 240-7941.

This story draws on reporting from NBC News with additional information from local health sources.